1. Field of the Invention
The present invention relates to a separation unit for separating recording paper from a photosensitive drum or a fixing roller of, e.g., an electronic copying machine.
2. Description of the Related Art
For example, an electronic copying machine has a photosensitive drum rotated in a predetermined direction. An image forming unit for forming a toner image, a transfer charger for transferring the toner image onto paper, a separation charger for electrically separating the paper attracted to the photosensitive drum by an electrostatic force during transfer of the image, and a cleaning unit for removing a residual toner which is not transferred to the paper and left on the surface of the photosensitive drum are arranged around the photosensitive drum. In addition, separation pawls are arranged between the separation charger and the cleaning unit.
Each separation pawl has a through hole. A bush to be loosely fitted on a support shaft is urged/fitted in the through hole. With this arrangement, each separation pawl is pivotally attached to the support shaft. A bracket is fixed to the support shaft so as to regulate the movement of the separation pawl in the axial direction. The separation pawls attached in this manner are pivoted by a contacting/separating mechanism so as to be brought into contact with or separated from the surface of the photosensitive drum, and at the same time are reciprocated by a reciprocating mechanism in the axial direction of the photosensitive drum. With this operation, the separation pawls mechanically separate the paper, which has been subjected to the transfer operation by the transfer charger and the electrically separating operation by the separation charger, from the photosensitive drum. This operation prevents occurrence of a jam due to the entrance of paper into the cleaning unit.
In such an attachment structure, however, if, for example, a separation pawl is damaged, the separation pawl alone cannot be detached from the support shaft without disassembling the overall separation unit. For this reason, a great deal of labor and time are required to replace the damaged separation pawl with a new one. In addition, a secondary accident may occur due to the disassembling operation of the separation unit.